A day with the partners
On 26 June 2025 the Center for Digital Trust ran a hands-on workshop on electronic identity for its partners. The morning, presented by Dr. Imad Aad, laid out the landscape: what the Swiss law on the E-ID requires, how those requirements map onto trust and threat models, and which cryptographic protocols can deliver them. This repository holds the afternoon: two Jupyter notebooks anyone can run with Docker or DevBox.
Two notebooks
The first walks through Swiyu, the Swiss government’s test environment for the E-ID: how it works, how C4DT’s taxonomy describes it, and where its current limits are.
The second looks past it, at two properties the next E-ID will need. Holder binding, so a credential can only be presented by the person it was issued to. Unlinkability, so two presentations cannot be tied to the same person. Building on Cloudflare’s ZKAttest, Ubique’s SHIELDS and Dock’s crypto library, it shows how an ECDSA signature can be proved alongside a BBS signature without being revealed.
Why it is here
This is what my three years on digital identity at C4DT were about: reading the specs and the papers, then proving that an idea holds in running code. The two crypto libraries below are the same thread, pulled further down.